Members of the party pioneered the use of theatrics and disruptive tactics in Hong Kong. Heckling and the throwing of projectiles have since become a frequent occurrence at Legislative Council and public meetings. Their members have been ejected from LegCo meetings on numerous occasions. At a Legislative council meeting on 15 October 2008, during the Policy Address given by then Chief ExecutiveDonald Tsang, party chairman Wong Yuk-man threw a banana at Tsang in protest at the means test of "fruit money" (Old Age Allowance) for the elderly.

At the opening of an exhibition at the Museum of History on 2 March 2011, Steve Wong Chun-kit, member of the League of Social Democrats rushed at Donald Tsang. Protesters also threw cooked rice at Tsang, as a symbol of the plight of the poor, but missed him. Tsang said his chest was hit by the protestor and had a medical check at the Queen Mary Hospital afterwards. Tsang denounced the protest, saying that violence was unacceptable in Hong Kong, where civilised behaviour and the rule of law were fundamental values. However Leung Kwok-hung said he did not see any physical contact between Tsang and protesters. Steve Wong was arrested and released on bail.[3]

At CY Leung's first question-and-answer session as Chief Executive at the Legislative Council in Hong Kong on 16 July 2012, "Long Hair" Leung Kwok-hung threw an effigy of Pinnochio at CY Leung.[4]

Leung Kwok-hung threw a cloud-shaped cushion at Financial SecretaryJohn Tsang during his budget report in the Legislative Council on 27 February 2013 to demand for a universal retirement protection scheme.[5]

At a political forum on 7 December 2013, one member was captured by the media throwing a Lufsig, a cuddly toy wolf at CY Leung.[6]

In May 2012, Leung Kwok-hung, the only LSD member in the Legislative Council joined a weeks-long filibuster staged by Albert Chan and Wong Yuk-man, who were LSD legislators but defected to the People Power, submitting 1306 amendments altogether to the Legislative Council (Amendment) Bill 2012, by which the government attempted to forbid resigning lawmakers from participating in by-elections as the government's response to the "Five Constituency Referendum movement" launched by the LSD in 2010. On the morning of 17 May 2012, Jasper Tsang Yok-sing, President of the Legislative Council adopt Article 92 of the Standing Order, which allows the president follow foreign parliament rules for unregulated behaviours to terminate the debate. In the end, all amendments were defeated and the Bill was passed.

In May 2013, the LSD and People Power staged a month-long filibuster by moving a total of 710 amendments on the Budget Appropriation Bill debate, to press for a universal pension scheme and a HK$10,000 cash handout to be included in John Tsang's budget.[7] The government warned that the service would shut down if the budget bill do not pass. Jasper Tsang ordered to end the filibuster on 13 May after 55 hours spent to debate 17 of the 148 amendments.[8] The Appropriation Bill was passed on 21 May 2013 with 684 amendments negatived.[9]

In the participation in the 2007 Chief Executive Election of Alan Leong, the League of Social Democrats refused to co-operate with the Democratic Party and the Civic Party and criticised the two parties for nominating Leong as Chief Executive candidate, saying that they are not qualified as democrats.[10] In the 2006 Election Committee election, the League was criticised by media for refusing to name a candidate in protest at the "small-circle election".

The LSD won six seats its first attempt in the election in the 2007 District Council elections. In late December 2007, the Vice-Chairman of the party, Lo Wing-lok, resigned after a controversy over the lack of documentation on the lease of the party headquarters. According to Lo, the premises belonged to an alleged triad member who claimed to be a merchant.[11]

The party was member of the Alliance for Universal Suffrage which consisted of all the pro-democracy groups to strive for the 2012 universal suffrage of the Chief Executive and Legislative Council. In response to the electoral reform package proposed by the government, the party joined hand with the Civic Party to launch the "Five Constituency Referendum" by having five legislators resigning and participating in a territory-wide by-election to demand genuine universal suffrage. The claim of by-election as referendum expectedly received serve attacks from the Beijing government and the pro-Beijing camp in Hong Kong as unconstitutional.[13] The Democratic Party refused to join the movement and sought for a less confrontational way to negotiate with Beijing. The movement was considered as failure with only 17.7 percent of the registered voters voted despite all three LSD legislators successfully returned to the LegCo.[13] The LSD strongly criticised the Democratic Party for its move to negotiate with Beijing and voted for the reform package and attacked the Democratic Party in the following 2010 July 1 march.

The party was also heavily devastated from the intra-party struggles. The former chairman Wong Yuk-man disagreed with the policies of the incumbent chairman Andrew To including the ways of dealing with the Democratic Party. On 24 January 2011, two of the three legislators of the party, Wong Yuk-man and Albert Chan quit the party with many party's leading figures, citing disagreement with leader Andrew To and his faction. About two hundreds of their supporters joined them, leaving the LSD in disarray.[14][15] Wong and Chan formed the People Power with other defected members and radical groups which aimed at sniping Democratic Party in the upcoming 2011 District Council elections.[16]

The party lost all its seats in the District Councils in the District Council elections in November, all four of the party's seats were swept by the pro-Beijing candidates, including that of Andrew To for Chuk Yuen North constituency. Twenty-three other League candidates also failed to win. Two days later, Andrew To resigned as chairman, to take responsibility for the loss, but pledged not to alter the League's ideology for the sake of winning elections.[17] Leung Kwok-hung replaced To as the Chairman of the LSD.